Graft copolymer of a linear polyester condensation product and nu-vinyl-3-morpholinone and process of making same



M y 1963 G. w. STANTON ETAL 3,090,766

CRAFT COPOLYMER OF A LINEAR POLYESTER CONDENSATION PRODUCT AND NVINYL3MORPHOLINONE AND PROCESS OF MAKING SAME Filed Jan. 7, 1959 IN V EN TORS. Gee/ 9e 14 57 0/1 zon BY Teddy 6. 770 /or e a see ree 3 a 9 Ice: Patented May 21, 1963 GRAFT CQPOLYh ER QF A LMEAR POLYESTER CONDENSATIUN PRODUCT AND N-VlNYL-3- lgdQR PHGLINONE AND PRGCESS OF MAKING Alvin George William Stanton, Williamsburg, Va., and Teddy G. Traylor, Concord, Calif., assignors to The Dow Chemical Qompany, Midland, Mich a corporation of Delaware Filed Jan. 7, 1959, Ser. N 785,333 6 Claims. (Cl. 260-4549 The present invention lies generally in the field of organic chemistry and contributes in particular to the art which pertains to synthetic, fiber-forming high polymers. More particularly, the present invention has reference to the provision of certain readily-dyeable graft or blocktype copolymers that are comprised of N-vinyl-3-morpholinone monomers, as hereinafter more fully described, polymerized on polyester polymer substrates.

Hydrophobic polymeric materials of varying origin are commonly employed in the manufacture of various synthetic shaped articles including films, ribbons, fibers, filaments, yarns, threads and the like and related structures, which hereinafter will be illustrated with particular reference to fibers. Polyester polymers may be utilized with great advantage for such purposes.

The fiber-forming, linear, resinous polyester polymer substrates that are contemplated as being adapted for employment in the practice of the present invention include any of the polyester high polymers of the type that are well known in the art and which are capable of being fabricated into useful fiber, film and related structures. Such fiber-forming polyester polymers, which, for convenience, will hereinafter be referred to as polyesters, are the essentially linen condensation products of glycols and polyglycols with dicarboxylic organic acids, which acids are ordinarily aromatic in nature, as, for eXample, dicarboxylic benzene and substituted benzene acids. In particular, the polyester polymers that are contemplated may be similar and analogous to those which have been described, amongst the other places, in United States Letters Patent No. 2,465,319. Specifically, there may be mentioned as especially desirable species of such materials the polyester polymers of terephthalic acid and propylene or ethylene glycol, or their mixtures. Polymer substrates in synthetic textile fiber form that are comprised of pol"- ester polymers of terephthalic acid and ethylene glycol are commercially available under the trademark Dacron. Films of the same polymer are commercially avail able under the trademark Mylar.

Difliculty, however, is often encountered in suitably dyeing synthetic hydrophobic fibers and the like that have been prepared from polyester polymers. This is especially the case when it is attempted to obtain relatively deeper shades of coloration in the finally dyed product.

Various techniques have been evolved for providing polyester polymer compositions of improved dyeability. The practice of such techniques has not always been completely satisfactory. Neither have the products achieved thereby always provided a completely suitable solution to the problems involved. For example, many of the fiber products which are prepared in accordance with the aboveidentified techniques known to the art often have inferior physical properties when they are compared with those prepared from unmodified polyesters. Also, such products, once they have been prepared, may not be as receptive as might be des red to a wide range of dyestuffs, due to inherent limitations in the materials capable of being employed for enhancing dye-receptivity.

It would be advantageous, and it is the chief aim and concern of the present invention, to provide polyester polymers which have been modified with certain graft or block copolymerized substituents so as to be exceptionally dyereceptive while being capable of being fabricated into fibers and the like and related shaped articles having excellent physical properties and other desirable characteristics commensurate with those obtained with the unmodified polyester substrates, and of the general order obtainable with Dacron, for example. This would possibilitate the manufacture of polyester polymer based fibers and the like articles having the highly desirable combination of attractive physical characteristics and substantial capacity for and acceptance of dyestufis.

To the attainment of these and related ends, a dyereceptive polymer composition that is adapted to provide shaped articles having excellent physical properties and characten'stics while being simultaneously receptive of and dyeable to deep and level shades of coloration with many of a wide variety of dyestuffs is, according to the present invention, comprised of a fiber-forming graft or block copolymer which consists of a polyester polymer substrate having a minor proportion of substituents graft copolymerized thereto that are comprised or consist essentially of polymerized units that have been derived from N-vinyl-3-morpholinone monomers a hereinafter more fully identified. schematically, the compositions may be structurally represented in the following manner:

wherein the interlinked PEST symbols represent the polyester polymer substrate or backbone trunk and the symbols VM connected thereto the substituent N-vinyl- 3-morpholinone graft coplymers branches of the N-vinyl- 3-morpholinone monomer provided thereon. As is apparent, the graft copolymerized N-vinyl-3-morpholinone units are attached to the polyester polymer substrate through or by means of carbon linkages, at least insofar as connection with the polymerized monomer units is concerned.

The graft copolymer substituent that is combined with the polyester polymer substrate lends the desired receptivity of and substantivity for various dyestuifs to the compositions while the polyester polymer trunk substrate that is so modified facilitates and secures the excellent physical properties and characteristics of the various shaped articles, including fibers into which the compositions may be fabricated. Advantageously, as mentioned, the polyester polymer substrate that is modified by graft copolymerization to provide the compositions of the invention is a resinous, fiber-forming condensation product of terephthalic acid with ethylene glycol, propylene glycol, or mmtures of such glycols.

It is usually beneficial, as has been indicated, for the graft copolymer compositions of the present invention to contain a major proportion of the polyester polymer trunk or substrate that has been modified with the substituent dye-receptive graft copolymer groups chemically attached thereto. As a general rule, for example, it is desirable for the graft copolymer to be comprised of at least about 80 percent by weight of the polyester polymer substrate. In many instances, it may be satisfactory for the graft copolymer composition to be comprised of between about 85 and 95 percent by weight of the polyester polymer substrate, particularly when it is Dacron or the like resinous product. In this connection, however, better dyeability may generally be achieved when the grafted copolymeric substituents are prepared under such conditions that they have relatively long chain lengths. Thus, it is usually preferable, when identical quantities of grafted substituents are involved for relatively fewer, but longer chain length grafts to be available than to have a greater number of substituents of relatively shorter chain length.

The N-vinyl-3-morpholinone monomer which is utilized to modify the acrylonitrile polymer substrates so as to provide the graft copolymer compositions of the present invention is of the general structure:

(N-vinyl-3 -morpholinone) This monomer, also for sake of convenience and brevity, is hereinafter referred to as VM. As is apparent, the monomeric VM may in many cases be utilized in combination or mixtures with certain of its homologues, such as the'various alkyl (particularly methyl and ethyl)-ringsubstituted-N-vinyl-3-morpholinones. VM may also be termed 4-vinyl-3-morpholinone.

The monomeric material employed for preparation of graft copolymers on preformed substrate polyester polymers in practice of the present invention is disclosed and described in United States Letters Patent No. 2,891,058.

As mentioned, the graft copolymer compositions of the invention have remarkably good dye-receptivity, particularly in view of their polyester polymer origin. In most cases, for example, the dye-receptivity of the graft copolymer'compositions of the present invention is improved to such an extent in comparison with unmodified polyester polymers, particularly unmodified Dacron, that a color differential of at least about 40 Judd units, as hereinafter illustrated, may readily be obtained between samples of the unmodified polyester polymer substrate and the graft copolymer compositions of the present invention, each of which has been dyed at a 4 percent dyeing according to conventional techniques with such a dyestutf as Calcodur Pink 2BL. This is a significant advantage when the compositions are fabricated into shaped article form, especially when they are prepared in a filamentary form suitable for use as a textile material.

Judd units are explained in an article by D. B. Judd in i the American Journal of Psychology, vol. 53, page 418 (1939). More information concerning Judd units appears in Summary on Available Information on Small Color Difierence Formulas, by Dorothy Nickerson, in the American Dyestuff Reporter, vol. 33, page 252, June 5, 1944. Also see interrelation of Color Specifications, by Nickerson, in The Paper Trade Journal, vol. 125,

page 153, for November 6, 1947.

As is well known, Calcodur Pink 2BL is a direct type of dye that has a Colour Index of 353. It is commercially obtainable under the indicated trade-designation. The same dyestuff, which is the sodium salt of 3,3'-disulphodiphenylurea 4,4 diazobis 2 -amino 8 naphthol 6- sulfonic acid, is actually available (usually under other commercial designations) from several sources. Calcodur Pink ZBL has the following structural formula, as

is given on page 88, Section A, Part IV of the Colour Index (1st Ed, 1924) published by the (British) Society of Dyers and Colourists:

slO Na NaOsS HO- NH: ITIH:

NaOaS HO- conventional procedures using acid, vat, acetate, direct,

naphthol, and sulfur dyes depending, of course, on the dye-attracting character of the graft copolymerized product of the particular monomer employed. Such dyestuffs, in addition to the particular variety mentioned, by way of didactic illustration, as Calcocid Alizarine Violet (Colour Index 61710, formerly Colour Index 1080), Sultanthrene Red 3B (Colour Index Vat Violet 2), Amacel Scarlet BS (Colour Index Disperse Red 1 or 11110), Calcodur Pink 2B1, (Colour Index 353, also more recently, Colour Index Direct Red Naphthol ASMX (Colour Index 35527), Fast Red TRN Salt (Colour Index Azoic Diazo 11), and Immedial Bordeaux G (Colour Index Sulfur Brown 12) may advantageously be employed for such purposes;

Other dyestuffs, by way of further illustration, that may be utilized beneficially on the N-vinyl-3-morpholinone graft copolymerized fiber products. of the invention include such direct cotton dyes as Chlorantine Fast Green SBLL (Colour Index Direct Green 27), Chlorantine Fast Red 73 (Colour Index Direct Red 81), Pontamine Green GX Cone. 125 percent (Colour Index Direct Green 6), Calcomine Black EXN Conc. (Colour Index Direct Black 38), Niagara Blue NR (Colour Index Direct Blue 151) and Erie Fast Scarlet 4BA (Colour Index Direct Red 24); such acid dyes as Anthraquinone Green GN (Colour Index Acid Green 25), Sulfonine Brown 2R (Colour Index Acid Orange 51), Sulfonine Yellow 26 (Colour Index Acid Yellow 40), Xylene Milling Black 2B '(C'olour Index Acid Black 26A), Xylene Milling Blue FF (Colour Index Acid Blue 61), Xyleen Fast Rubine 3GP PAT (Colour Index Acid Red 57), Calcocid Navy Blue R Conc. (Colour Index Acid Blue Calcocid Fast Blue BL (Colour IndexFast Blue 59), Calcocid Milling Red 3R (Colour Index Acid Blue 151), Alizarine Levelling Blue 2R (Colour Index Acid Blue 51), Amacid Azo Yellow G Extra (Colour Index Acid Yellow 63); such mordant-acid dyes as Alizarine Light Green GS (Colour Index Acid Green 25); such basic dyes as Brilliant Green Crystals (Colour Index Basic Green 1) and Rhodamine B Extra S (Colour Index Vat Blue 35); such vat dyestufi's as Midland Vat Blue R Powder (Colour Index Vat Blue 35), Sulfanthrene Brown G Paste (Colour Index Vat Brown 5), Sulfanthrene Blue 23 Dbl paste (Colour Index Vat Blue 5), and Sulfanthrene Red 3B paste (Colour Index Vat Violet 2); various soluble vat dyestuffs; such acetate dyes as Celliton Fast Brown 3RA Extra CF (Colour Index Dis,-'

persed Orange Celliton Fast Rubine BA CF (Colour Index Dispersed Red 13 Artisil Direct Red 3B? and Celanthrene Red 3BN Cone. (Both Colour Index Dispersed Red 15, Celanthrene Pure Blue BRS 400 percent (Colour Index Dispersed Blue 1) and Acetamine Yellow N (Colour Index Dispersed Yellow 32); B-Naphthok-Z- chloro-4-nitroaniline, an azoic dye; such sulfur dyes as Katigen Brilliant Blue GGS High Cone. (Colour Index Sulf. Blue 9) and lndo Carbon CLGS (Colour Index Sulf. Blue 6); and various premetallized dyestuffs.

The dyed products, especially textile fiber products, are generally lightfast and are well imbued with good resistance to crocking. In addition, dyed textile fiber products comprised of the compositions of the invention exhibit remarkable washfastness, despite repeated exposure and subjection to washing, laundering and dry cleaning treatments.

A shaped filamentary article prepared from -a dyereceptive composition in accordance with the present invention is schematically illustrated in the sole FIGURE of the hereto annexed drawing.

The dye-receptive graft copolymers of the present invention may be prepared and provided by swelling or impregnating the polyester polymer substrate with the monomeric substance then polymerizing the monomer in situ in the polymer substrate. Advantageously, this may be accomplished when the substrate is in the form of an already shaped article, such as a fiber or filamentary structure. Beneficially, the graft copolymerization of the impregnated monomer may be accomplished and facilitated with the assistance of a pobmerization catalyst or catalyzing influence which, preferentially, interacts with the substrate in order to establish or form grafting sites thereon and simultaneously or subsequently initiate the graft copolymerization. As a practical matter, it is generally most desirable to form the graft copolymer compositions in such manner. Most of the free radical generating chemical catalysts, including peroxideand persulfate catalysts, may be utilized for the desired graft copolymerization. It may often be exceptionally advantageous, however, to accomplish the graft copolymerization by subjecting the monomer-impregnated polyester polymer substrate to a field of high energy radiation in order to efficiently provide an effectively attached graft copolymer of the polymerized monomeric impregnant on the hydrophobic polyester polymer substrate.

The monomer may be intimately impregnated in the polyester polymer substrate in any desired manner prior to the graft copolymerization. Thus, the monomer may be directly applied, particularly when it has a swelling effect on the substrate, or it may be applied from dispersion or solution in suitable liquid vehicles, preferably those tending to swell the polymer, until a desired monomer content has been obtained. Ordinarily it is advantageous for the monomer to be diluted in a solvent or dispersant vehicle so as to provide a treating bath in which to swell or impregnate the polyester polymer substrate with the latter being immersed in the bath for a sufficient period of time to attain a desired monomer content adequate for the intended purpose. The polyester polymer substrate, as has been mentioned, may be in any fabricated or unfabricated form. Unfabricated graft copolymer compositions in accordance with the present invention may be converted to shaped articles by any desired technique adapted for such purpose with conventional polymers. It is generally desirable and of signii cant advantage, however, to impregnate a preformed article, such as a textile fiber of the polyester polymer (or a cloth or fabric comprised thereof) with the monomer in order to prepare the graft copolymer compositions of the invention.

In this connection, particularly when preformed fiber structures are involved, the article may be in any desired state of formation for the impregnating and graft copolymerizing modification. Thus fibers and films may be 6 treated before or after any stretch has been imparted thereto. In addition, they may be in various stages of orientation, or in a gel, swollen or dried condition.

The impregnation and succeeding polymerization may, in general, be effected at temperatures between about 0 C. and about 200 C. for periods of time ranging up to 4 or more hours. The most suitable conditions in each instance may vary according to the nature and quantity of the specific monomeric impregnant involved and the graft copolymerizing technique that is utilized. For example, when chemical catalysts -are employed for purposes of forming the graft copolymer, a temperature of between about 50 and C. for a period of time between about 15 and 45 minutes may frequently be advantageously employed for the purpose. Under the infiuence of high energy radiation, however, it may frequently be of greatest advantage to accomplish the graft copolymerization at temperatures between about 20 and 60 C. utilizing relatively low dose rates and total dosages of the high energy for the desired purpose. Graft copolymerization on pre-activated substrates may ordinarily be accomplished by simply exposing the activated substrate to the monomer (preferably in concentrated solution) at an elevated temperature until the graft copolymerized substituents have formed on the substrate.

When the graft copolymer compositions are prepared from preformed or already shaped polyester polymer substrates that are successively impregnated with the monomer, which is then graft copolymerized in situ in the shaped article, excess monomer, if desired, may be squeezed out or removed in any suitable manner prior to efiecting the graft copolymerization.

The chemical free radical generating catalysts which may be employed with greatest advantage in the preparation of the graft copolymer compositions of the present invention include hydrogen peroxide, benzoyl peroxide, cumene hydroperoxide, ammonium or potassium persulfate and the like. Such catalysts may be used in conventional quantities to eifect the graft copolymerization. When they are utilized, it is of greatest benefit to incorporate them in the impregnating solution of the monomer that is used.

The high energy radiation which may be employed for inducing the graft copolymerization for the prepara tion of the graft copolymers of the present invention is of the type which provides emitted particles or photons having an intrinsic energy of a magnitude which is greater than the planetary electron binding energies that occur in the graft copolymerizing materials. Such high energy radiation is available from various radioactive substances which provide beta or gamma radiation as, for example, radioactive elements including cobalt-60 and cesium-l37, nuclear reaction fission products and the like. If it is preferred, however, high energy radiation from such sources as electron beam generators, including linear accelerators and resonant transformers, X-ray generators and the like may also be utilized. It is beneficial to employ the high energy radiation in a field of at least about 40,000 roentgens per hour intensity. A roentgen, as is commonly understood, is the amount of high energy radiation as may be provided in a radiation field which produces in one cubic centimeter of air at 0 C. and 760 millimeters of absolute mercury pressure, such a degree of conductivity that one electrostatic unit of charge is measured at saturation (when the secondary electrons are fully utilized and the wall effect of the chamber is avoided). It is most desirable, incidentally, to graft copolymerize all or substantially all of the monomeric impregnant to and with the polyester polymer substrate being modified in order to provide the compositions of the present invention. In addition, as has been indicated, particularly when pre-activation of the substrate is performed, ultra-violet light may also be employed as the high energy radiation form. Preactivation or graft site A sample of cloth woven from polyethylene terephthalate (Dacron) yarn is scoured and soaked for 7 about an hour at 75 C. in a 50 percent aqueous solution of monomeric N-vinyl-3-morpholinone (VM). The polymer is thereby impregnated with about 15 percent of the monomer. The wet fiber is then exposed at a distance of about 1 centimeter from a Machlett OEG-SO tube that is operated at 50,000 volts at 50 milliamperes. The exposure is continued for about 25 minutes. The irradiated yarn is then washed thoroughly with water, dried, scoured and dyed for one hour at the boil with 4 percent (on the weight of the fiber and according to the conventional technique) of Calcodur Pink 2BL. A deep and level shade of pink is obtained in the irradiated portion. The remainder of the cloth sample, however, is not even stained by the dyestuff.

The degree of dye-receptivity of the fiber in the irradiated portion of the cloth is evaluated by spectrophotometrically measuring the amount of monochromatic light 'having a wave length of about 520 millimicrons from a standard source that was reflected therefrom. A numerical reflectance value is thereby obtained which represents the relative comparison of the amount of light that is reflected from the dyed portion of the sample with that which is reflected from a standard White tile reflector, having an arbitrarily assigned reflectance value of 316.

Lower reflectance values are an indication of better dye-receptivity in a fiber or other shaped polymer article. For example, a reflectance value of about 20-50 for synthetic hydrophobic fibers of the type that may be benefited by the practice of the method of the present invention (when they are dyed with 4 percent Calcodur Pink 2BL) is generally considered by those skilled in the art to represent a degree of dye-receptivity that meets or exceeds the most rigorous practical requirements and is ordinarily assured of receiving general commercial acceptance and approval.

The radiated and dyed colored portion of the cloth has a reflectance value of about 40. The non-irradiated and non-stained portion of the cloth sample has a reflectance value of about 140.

The color yield and difierential between the irradiated and non-stained portions of the cloth sample is also. determined by a similar reflectance method using the entire visible spectrum from a standard light source and a photoelectric measuring means to indicate the amount of reflected light obtained from each portion of the cloth sample when they are separately exposed to the light source. A numerical value may be calculated in Judd units to indicate the amount of color diflerence between samples of the same material in an undyed (or lightly dyed) and a dyed condition. A greater numerical value of Judd units, which are frequently employed in the art for measuring color differentials, is an indication of less reflectance and better dye-receptivity and retention in given samples of dyed and undyed polymeric articles, such as cloth or fibers.

The color diflerence between the dyed and undyed portion of the partially radiated cloth sample is about 65 Judd V The graft copolymerized fiber product is also dyed well to deep and level shades of coloration with Calcocid Alizarine Violet, an acid type of dyestufl.

Illustration B for impregnating the cloth substrate. About 20 percent 8 of the VM is thereby incorporated in the cloth. The reflectance value of the finally dyed, radiated portion of the cloth sample is about 20. Its color differential over the undyed portion is about 75 Judd units.

Illustration C The procedure of Illustration A is againrepeated excepting to use a percent aqueous solution or the monomer. The quantity of impregnant in the cloth is about 25 percent. The results are about the same as in the second illustration.

Illustration D The procedure of Illustration C is repeated excepting to irradiate a portion of the cloth with adosage of 0.25 mrep. of 10 million electron volt (mev.) electrons from a linear accelerator. The irradiated portion of the cloth displays a significant improvement in its dyeability with Calcodur Pink 2BL.

Illustration E The procedure of Illustration D is repeated excepting to impart a 10 mrep. (million roentgen equivalent physicals) dosage of 1 mev. electrons at a 70 mrep, per minute rate from a Van de Graafl electrostatic generator to the radiated portion of the cloth sample which, after washing, is found to contain about 4 percent of poly-N- vinyl-3-morpholinone (PVM) by nitrogen analysis. Its dyeability with Calcodur Pink 2B1. is noticeably improved in the irradiated portion. Its dyeability therein with Amacel Scarlet BS is even more pronounced in comparison with that of the non-irradiated portion. When the procedure is again repeated with another cloth sample in which only a l mrep. dose is effected, the improvement in dyeability is not so great as when the larger dosage is employed.

. Illustration F The procedure of Illustration E is repeated, excepting to subject the cloth sample to irradiation in the electron beam of the linear accelerator at a rate of about 40 thousand rep. per minute. Similar results are obtained.

Illustration H A small sample (about 0.1 gram) of Dacron cloth is immersed in a solution of about 2.5 grams of 2-sulfoethyl methacrylate dissolved in a mixture of about 5 milliliters of monomeric VM and 5 ml. of N-methyl pyrrolidone for 1 5 minutes at 70 C. The polymer is impregnated with about 20 percent of the monomer mixture. After the impregnation, the. excess monomer solution is permitted to drain from the cloth and the impregnated sample is then flushed with nitrogen and subsequently irradiated by exposure at room temperature to a high energy, X-ray radiation beam from a Van de Graaff Electrostatic Generator operating under a potential of 2 million electron volts with a 250 microampere beam current impinging on a tungsten target. The monomer impregnated cloth sample is subjected to the high energy until a total dosage of about 5 mrep. has been obtained. The sample is rinsed, dried and dyed with 4 percent Sevron Brilliant Red 4G (Colour Index Basic Red 14) in the conventional manner. A deep and level shade of coloration is obtained in the graft copolymerized product. In comparison, the unmodified yarn can be dyed to only thefaintest degree with the same dyestulf.

Illustration 1 A small square of Dacron cloth similar to that employed in the first illustration is immersed in monomeric VM and the mixture heated for 15 minutes to a temperature of about 70 C. The monomer impregnated sample is then permitted to drain free of excess liquid and is subsequently transferred to a polyethylene hag wherein it is flushed with nitrogen and sealed. It is then given about a 20 mrep. dose of high energy irradiation with a Van de Graalf Generator operating in the manner set forth in the preceding illustration. The irradiated cloth sample, after being thoroughly washed with water and dried, shows excellent receptivity to Calcodur Pink 2BL when dyed therewith in the conventional manner.

Results similar to the foregoing may also be obtained when any other of the mentioned monomeric alkyl-ringsubstituted homologues of N-vinyl-3-morpholinone or mixtures thereof are utilized in place of VM in a similar manner to that set forth in the above illustrations and when graft copolymers are prepared with such monomers on unfabricated forms of the polyester polymer substrate or when the graft copolymerization is accomplished with other varieties of polyester polymers besides those used for purposes of didactic exemplification.

What is claimed is:

l. Dye-receptive graft copolymer composition comprised of (1) a fiber-forming, synthetic, linear polyester which is a condensation product of glycol and a dicarboxylic organic acid and contains recurring ester groups as an integral part of the main polymer chain separated by at least two carbon atoms having along its chain, as graft copolymerized substitutents thereon, up to about 20 weight percent, based on graft copolymer composition weight, of (2) polymerized N-vinyl-3morpholinone.

2. The composition of claim 1, wherein said polyester has between about 5 and 15 percent by weight, based on the Weight of the composition, of said graft copolymerized substituents attached thereto.

3. The composition of claim 1, wherein said polyester is a resinous condensation product of terephthalic acid and a glycol of from 2 to 3 carbon atoms.

4. A filamentary shaped article comprised of the composition of claim 3.

5. A filamentary shaped article comprised of the composition of claim 1.

6. Method for the preparation of a dye-receptive polymer composition which comprises mixing a minor proportion of N-vinyl-3-morpholinone monomer with a preformed, fiber-forming, synthetic, linear polyester which is a condensation product of a glycol and a dicarboxylic organic acid and contains recurring ester groups as an integral part of the main polymer chain separated by at least two carbon atoms; then subjecting said mixture to polymerization at a temperature between about 0 C. and 200 C. until up to about 20 weight percent, based on resulting composition weight, of said N-vinyl-3-morpholinone monomer is polymerized as graft copolymer substituents on said linear polyester.

References Cited in the file of this patent UNITED STATES PATENTS 2,818,362 Drechsel Dec. 31, 1957 2,891,058 Walles et a1. June 16, 1959 2,948,708 Walles et al Aug. 9, 1960 

1. DYE-RECEPTIVE GRAFT, COPOLYMER COMPOSITION COMPRISES OF (1) A FIBER-FORMING, SYNTHETIC, LINEAR POLYESTER WHICH IS A CONDENSATION PRODUCT OF GLYCOL AND A DICARBOXYLIC ORGANIC ACID AND CONTAINS RECURRING ESTER GROUPS AN AN INTEGRAL PART OF THE MAIN POLYMER CHAIN SEPARATED BY AT LAST TWO CARBON ATOMS HAVING ALONG ITS CHAIN, AS GRAFT COPOLYMERIZED SUBSTITUENTS THEREON, UP TO ABOUT 20 WEIGHT PERCENT, BASED ON GRAFT COPOLYMER COMPOSITION WEIGHT, OF (2) POLYMERIZED N-VINYL-3-MORPHOLINONE. 